
/**
 *  Class: TimestampConversion
 *  Author: Tikky
 *  Date: 2018/12/21.
 *  Description: 时间格式化
 *  @param  {string}        dateStr   输出格式
 *  @param  {string|number} timestamp 时间
 *  @return {string}        timeText 输出时间
 */
function TimestampConversion(dateStr, timestamp) {
    let jsdate = ((timestamp) ? new Date(timestamp * 1000) : new Date());
    let pad = function (n, c) {
        if ((n = n + '').length < c) {
            return new Array(++c - n.length).join('0') + n;
        } else {
            return n;
        }
    };
    // let txt_weekdays = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];
    let txt_weekdays = ['周日', '周一', '周二', '周三', '周四', '周五', '周六'];
    let txt_ordin = {
        1: 'st',
        2: 'nd',
        3: 'rd',
        21: 'st',
        22: 'nd',
        23: 'rd',
        31: 'st'
    };
    let mon_full_names = ['', 'January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];
    let f = {
        // Day
        d: function () {
            return pad(f.j(), 2);
        },
        D: function () {
            return f.l().substr(0, 3);
        },
        j: function () {
            return jsdate.getDate();
        },
        l: function () {
            return txt_weekdays[f.w()];
        },
        N: function () {
            return f.w() + 1;
        },
        S: function () {
            return txt_ordin[f.j()] ? txt_ordin[f.j()] : 'th';
        },
        w: function () {
            return jsdate.getDay();
        },
        z: function () {
            return (jsdate - new Date(jsdate.getFullYear() + '/1/1')) / 864e5 >> 0;
        },

        // Week
        W: function () {
            let a = f.z(),
                b = 364 + f.L() - a;
            let nd2, nd = (new Date(jsdate.getFullYear() + '/1/1').getDay() || 7) - 1;
            if (b <= 2 && ((jsdate.getDay() || 7) - 1) <= 2 - b) {
                return 1;
            } else {
                if (a <= 2 && nd >= 4 && a >= (6 - nd)) {
                    nd2 = new Date(jsdate.getFullYear() - 1 + '/12/31');
                    return date('W', Math.round(nd2.getTime() / 1000));
                } else {
                    return (1 + (nd <= 3 ? ((a + nd) / 7) : (a - (7 - nd)) / 7) >> 0);
                }
            }
        },

        // Month
        F: function () {
            return mon_full_names[f.n()];
        },
        m: function () {
            return pad(f.n(), 2);
        },
        M: function () {
            return f.F().substr(0, 3);
        },
        n: function () {
            return jsdate.getMonth() + 1;
        },
        t: function () {
            let n;
            if ((n = jsdate.getMonth() + 1) == 2) {
                return 28 + f.L();
            } else {
                if (n & 1 && n < 8 || !(n & 1) && n > 7) {
                    return 31;
                } else {
                    return 30;
                }
            }
        },

        // Year
        L: function () {
            let y = f.Y();
            return (!(y & 3) && (y % 1e2 || !(y % 4e2))) ? 1 : 0;
        },
        //o not supported yet
        Y: function () {
            return jsdate.getFullYear();
        },
        y: function () {
            return (jsdate.getFullYear() + '').slice(2);
        },

        // Time
        a: function () {
            return jsdate.getHours() > 11 ? 'pm' : 'am';
        },
        A: function () {
            return f.a().toUpperCase();
        },
        B: function () {
            // peter paul koch:
            let off = (jsdate.getTimezoneOffset() + 60) * 60;
            let theSeconds = (jsdate.getHours() * 3600) + (jsdate.getMinutes() * 60) + jsdate.getSeconds() + off;
            let beat = Math.floor(theSeconds / 86.4);
            if (beat > 1000) beat -= 1000;
            if (beat < 0) beat += 1000;
            if ((String(beat)).length == 1) beat = '00' + beat;
            if ((String(beat)).length == 2) beat = '0' + beat;
            return beat;
        },
        g: function () {
            return jsdate.getHours() % 12 || 12;
        },
        G: function () {
            return jsdate.getHours();
        },
        h: function () {
            return pad(f.g(), 2);
        },
        H: function () {
            return pad(jsdate.getHours(), 2);
        },
        i: function () {
            return pad(jsdate.getMinutes(), 2);
        },
        s: function () {
            return pad(jsdate.getSeconds(), 2);
        },
        // u not supported yet

        // Timezone
        // e not supported yet
        // I not supported yet
        O: function () {
            let t = pad(Math.abs(jsdate.getTimezoneOffset() / 60 * 100), 4);
            if (jsdate.getTimezoneOffset() > 0) t = '-' + t;
            else t = '+' + t;
            return t;
        },
        P: function () {
            let O = f.O();
            return (O.substr(0, 3) + ':' + O.substr(3, 2));
        },
        //T not supported yet
        //Z not supported yet

        // Full Date/Time
        c: function () {
            return f.Y() + '-' + f.m() + '-' + f.d() + 'T' + f.h() + ':' + f.i() + ':' + f.s() + f.P();
        },
        //r not supported yet
        U: function () {
            return Math.round(jsdate.getTime() / 1000);
        }
    };

    // dateStr = "Y/m/d H:i:s" ;
    return dateStr.replace(/[\\]?([a-zA-Z])/g, function (t, s) {
        let ret;
        if (t != s) {
            // escaped
            ret = s;
        } else if (f[s]) {
            // a date function exists
            ret = f[s]();
        } else {
            // nothing special
            ret = s;
        }
        return ret;
    });
}

export default TimestampConversion;
